We extend our previous analytic existence of a symmetric periodic
simultaneous binary collision orbit in a regularized fully symmetric equal mass
four-body problem to the analytic existence of a symmetric periodic
simultaneous binary collision orbit in a regularized planar pairwise symmetric
equal mass four-body problem. We then use a continuation method to numerically
find symmetric periodic simultaneous binary collision orbits in a regularized
planar pairwise symmetric 1, m, 1, m four-body problem for m between 0 and 1.
Numerical estimates of the the characteristic multipliers show that these
periodic orbits are linearly stability when 0.54≤m≤1, and are
linearly unstable when 0<m≤0.53.Comment: 6 figure